The Portuguese National Programme for Dams with High Hydropower Potential
(PNBEPH) foresees the construction of 10 new hydropower installations in several river
basins. Among other relevant impacts that fall out of the scope of this study, hydropower
projects can have an important impact on water quality - mainly on hydro-morphological
conditions for aquatic life to sustain.
According to the Water Framework Directive (WFD), the deadline for achieving a good
status of surface waters is 2015. In the meantime, Member States should avoid taking
action that could jeopardize the achievement of the objectives of the directive, notably the
general objective of good status of water bodies. Derogations for building new
infrastructure projects (notably dams) are possible under Article 4.7, if certain strict
conditions are met and an assessment is done according to these conditions. These
conditions include amongst others that there are no significantly better environmental
options, the benefits of the new infrastructure outweigh the benefits of achieving the WFD
environmental objectives and all practicable mitigation measures are taken to address the
adverse impact of the status of the water body. In addition, the justification for those
modifications should be included in the river basin management plans due to be adopted
in December 2009 after public consultation.